diff options
| author | Jason Wang <jasowang@redhat.com> | 2021-04-15 03:31:41 -0400 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2021-05-03 04:55:51 -0400 |
| commit | 9e3bb9b79a7131a088cfffbdcc30e747dad9d090 (patch) | |
| tree | 00ba646956553de932547a6d7f698012ac8ed00a /drivers/virtio | |
| parent | 122b84a1267aec28ab929edae1ac700a03fb65e0 (diff) | |
| download | linux-9e3bb9b79a7131a088cfffbdcc30e747dad9d090.tar.gz linux-9e3bb9b79a7131a088cfffbdcc30e747dad9d090.tar.xz | |
virtio_pci_modern: introduce helper to map vq notify area
This patch factors out the logic of vq notify area mapping. Following
patches will switch to use this common helpers for both virtio_pci
library and virtio-pci vDPA driver.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210415073147.19331-2-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>
Diffstat (limited to 'drivers/virtio')
| -rw-r--r-- | drivers/virtio/virtio_pci_modern_dev.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c index cbd667496bb1..28cb5847fafa 100644 --- a/drivers/virtio/virtio_pci_modern_dev.c +++ b/drivers/virtio/virtio_pci_modern_dev.c @@ -593,6 +593,41 @@ u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev, } EXPORT_SYMBOL_GPL(vp_modern_get_queue_notify_off); +/* + * vp_modern_map_vq_notify - map notification area for a + * specific virtqueue + * @mdev: the modern virtio-pci device + * @index: the queue index + * + * Returns the address of the notification area + */ +void *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev, + u16 index) +{ + u16 off = vp_modern_get_queue_notify_off(mdev, index); + + if (mdev->notify_base) { + /* offset should not wrap */ + if ((u64)off * mdev->notify_offset_multiplier + 2 + > mdev->notify_len) { + dev_warn(&mdev->pci_dev->dev, + "bad notification offset %u (x %u) " + "for queue %u > %zd", + off, mdev->notify_offset_multiplier, + index, mdev->notify_len); + return NULL; + } + return (void __force *)mdev->notify_base + + off * mdev->notify_offset_multiplier; + } else { + return (void __force *)vp_modern_map_capability(mdev, + mdev->notify_map_cap, 2, 2, + off * mdev->notify_offset_multiplier, 2, + NULL); + } +} +EXPORT_SYMBOL_GPL(vp_modern_map_vq_notify); + MODULE_VERSION("0.1"); MODULE_DESCRIPTION("Modern Virtio PCI Device"); MODULE_AUTHOR("Jason Wang <jasowang@redhat.com>"); |